Im having some issues with the clutch slipping on this 74 DT250. To keep this short i have already played with the adjustment a ton, i have the correct plate count+ new plates and springs but somebody had it set up like a 360. I believe what somebody did was they took a 360 clutch off and tossed it on this 250. In pictures 1 and 2 i believe that is what should be on the clutch + the 250 clutch boss which i dont have. The screw you see does not thread into the current boss. The current boss takes the smaller screws as seen in the 3rd pic. Just need to know the correct set up and if anyone has a 74 DT250 clutch boss their willing to part with or even trade for the one i just bought on ebay?

 
 
 
  

Probably just me but I don't understand which part you're asking for...  Part in your first pic (pressure plate) doesn't have any threads that I remember?

In 1974 the 250 and 360 had different primary gear ratios so I'm not sure someone could throw in a 360 clutch? 

I think it was the earlier models that had the smaller threads...  have you checked VIN to see if 1974 engine?  Maybe someone installed an earlier clutch?

Also no expert but from side view (2nd pic) disk stack looks awfully short.  Usually frictions are close to top of outer hub.

Hopefully someone more familiar with 250/360 of that era will jump in and help.

The pressure plates are not threaded, the bolts go through and screw into the clutch boss which i dont have a picture of the boss uploaded.

I believe you can swap bosses and pressure plates regardless of the year on the 250 and 360s however the rod length and depth/shallowness of the clutch boss and pressure plate is whats in question and i dont have a spare DT250 boss to compare unless i wanna tear my running 74 DT250 down which i dont lol. That bike does have the pressure plate as seen in pic 1 which is how i was able to get this far. Pic 3 is how its currently set up.

I already ran the vin number it is a 74 DT250.

I believe you are correct about the earlier models using the smaller threaded screws to hold the pressure plate on. I think in 74 thats when it changed.

As for the stack of plates in pic 3 ive noticed that too. The 360 takes more clutch plates than the 250 and im confident that the clutch boss thats mounted AND the one i just bought is off a 360 because they both take the smaller screws. Im thinking that the 360 boss is probably a little bit taller so that the extra plates can fit however thats no good for a 250. I tried adding another plate but its a no go. Im confident that all i need is a 74 DT250 clutch boss to fix this but i wanted to get some 2nd opinions first and after buying one that is SUPPOSED to be for a 74 DT250 off ebay i dont really wanna deal on there again.
Does anyone out there happen to have both a 360 and 250 clutch boss laying around they can measure?

Last pic looks like the earlier "73 motor or was that what you mean't to show using the old style screws with 5mm thread. Clutch boss for the 6mm bolts have longer full length spring posts where as the old style screws were half of the post combined. That reads confusing sorry.

I just took a look at an original 1974 parts list and it shows the 1974 DT250 used the earlier clutch pressure plate 214-16351-00 and screws 137-16337-01 so the second picture looks correct.

I'd say your best option is to take off pressure plate and lay out all the discs the way they belong.... looks like a spacer goes on first 214-16332-00.... then what I believe is a thick steel 214-16324-00... then first of 7 frictions 168-16321-00... alternating with 7 steels 371-16325-00 ending with a steel.

(Note that some of the part numbers may have been superseded.)

That was my conclusion as well regarding the correct pressure plate and screws Mark. Pic 1 and 2 is what should be on the bike i believe but i cant mount those because the clutch boss is different and i have no way of telling the difference between the 2 bosses other than the screw sizes/shape.

You can see the 1 bolt in my hand has a phillips and hex head plus the thread size is bigger VS the ones you see mounted in pic 3 which have a smaller thread size and only a phillips head plus a shoulder the springs coil around.

Im looking in the service manual in the tech library as well as the diagram pulled up on babbitts and im not seeing that spacer ring you mentioned 214-16332-00. I know what ring your talking about because my 73 360 takes that. I know around this era the 250 and 360 do tend to share parts diagrams are you sure that spacer ring doesnt go in a 74 DT360? My good running 74 DT250 as i recall does not have that spacer ring in the clutch and it works great.

I currently have it set up like in the diagram starting with the thick metal plate 214-16324-00-00 then a friction and then the regular metal and friction plates 371-16325-00-00 and 5y1-16331-01-00. I think im at the point where if i am correct about this not getting the spacer ring then i need the correct boss.

Pic one and two is NOT what should be on the bike from what I see? Even Service Manual pic shows pic 3 style clutch.

The larger bolt and different hub might have happened in 1975.

Take a look in Tech Library for 1974 parts list in Japanese... It's extremely clear about which parts go to the 250 and which go to the 360. Maybe it's not correct as some diagrams aren't... but it does clearly show and LIST a spacer which if missing would cause a slipping issue.

Partzilla diagram is confusing and pretty sure it's not correct. 250 parts are mostly "0" on the list instead of a number corresponding to the diagram.

Well in the service manual they may have just shown the DT360 picture to show us how its taken apart because the service manual has both the 250 and 360 listed.
My running 74 DT250 has the set up from pics 1 and 2 works just fine. Im pretty sure that one does not have the spacer but id have to tear into it again to know for sure.

I see the Japanese parts list you mentioned and the spacer in both the clutch diagrams but i cant read Japanese. There may be a note saying #9 the spacer is only used in the 250 or 360 like it does in the service manual for a 73 RT360 as seen on page 43 in that manual. Anyone read Japanese? lol
 
Babbitts diagram doesnt show the spacer i find their diagrams to only be so accurate.

I think i have a spare spacer in a parts 360 motor i can take out and try. I got a friend who has a 74 DT360 that needs transmission work. Ill reach out to him and tear into his clutch to compare with mine. While im at it i might just pop the cover off on my running 74 DT250 so i can compare all 3 bikes. Will get to the bottom of this one way or another!

Try an extra steel clutch plate at the bottom of the stack to thicken up the clutch pack so the boss doesn't bottom out before it can squeeze the pack. It worked for me when I had the same problem. I can lock the front brake and smoke the back tire now that the clutch works so good.
doug

An excellent suggestion! i did think of doing something like that but was afraid of having the metal on metal clutch plates together. I didnt wanna cause damage or create another problem. I may give that a shot and see how she does.